Medium Lockout
28 on Potterton Performa 24 Eco HE

Your boiler is struggling to monitor the temperature of your hot water, which usually means it won't be able to provide consistent hot water to your taps.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

Book a service

This fault should be looked at by a Gas Safe engineer within the next week or two. It may get worse if left.

Technical description

Fault on Hot Water Sensor

What causes this fault?

This fault occurs when the internal sensor responsible for measuring the temperature of your tap water fails or sends an unreadable signal back to the main control board. The most common reason is that the sensor has physically degraded over time or developed an electrical short due to constant heat cycles. In some cases, it can also be triggered by a loose connection or damaged wiring between the sensor and the boiler’s computer.

Engineer required

This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

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